Here's another stab at enabling QEMU on systems with pathologically reduced IPA ranges such as the Apple M1 (previous version at [1]). Eventually, we're able to run a KVM guest with more than just 3GB of RAM on a system with a 36bit IPA space, and at most 123 vCPUs. This series does a few things: - decouple the enabling of the highmem PCIe region from the highmem attribute - introduce a new attribute to control the enabling of the highmem GICv3 redistributors - correctly cap the PA range with highmem is off - generalise the highmem behaviour to any PA range - disable both highmem PCIe and GICv3 RDs when they are outside of the PA range This has been tested on an M1-based Mac-mini running Linux v5.16-rc6 with both KVM and TCG. * From v2: - Fixed checking of the maximum memory against the IPA space - Fixed TCG memory map creation - Rebased on top of QEMU's 89f3bfa326 - Collected Andrew's RBs, with thanks [1] https://lore.kernel.org/r/20211003164605.3116450-1-maz@xxxxxxxxxx Marc Zyngier (5): hw/arm/virt: Key enablement of highmem PCIe on highmem_ecam hw/arm/virt: Add a control for the the highmem redistributors hw/arm/virt: Honor highmem setting when computing the memory map hw/arm/virt: Use the PA range to compute the memory map hw/arm/virt: Disable highmem devices that don't fit in the PA range hw/arm/virt-acpi-build.c | 12 +++---- hw/arm/virt.c | 67 ++++++++++++++++++++++++++++++++++------ include/hw/arm/virt.h | 4 ++- 3 files changed, 67 insertions(+), 16 deletions(-) -- 2.30.2
